Anthocyanin Composition of Red Raspberry Juice: Influences of Cultivar, Processing, and Environmental Factors

The anthocyanin and anthocyanidin pigment profiles of 46 authentic red raspberry juice samples were determined by HPLC. Total anthocyanin pigment content and percent polymeric color were also determined. This generated a database incorporating influences of cultivar, geographic origin, maturity, processing, and mold contamination. Cultivars exhibited characteristic patterns distinguished by quantitative rather than qualitative differences. Total pigment ranged from 4 to 1,102 mg/L. Commercial red raspberry juice concentrates (14) were also analyzed. Two were shown to be adulterated because of the presence of delphinidin glycosides. Three samples contained high amounts of polymerized pigments, indicating a history of processing or storage abuse.     

高压脉冲电场(PEF)处理对红莓花色苷提取过程的影响

研究了3.0 kV/cm高压脉冲电场(PEF)处理对红莓花色苷提取过程的影响。结果表明:3.0 kV/cmPEF处理对红莓果实液泡细胞膜的损伤比冷冻-解冻过程的机械损伤更显著,60~420个脉冲数的PEF处理能使甘露醇等渗溶液的电导率由65μs/cm增加至490μs/cm,明显加快花色苷的传质速率;用3.0 kV/cm PEF处理420个脉冲后,用酸化甲醇提取15 min,可使花色苷的提取率达到54.24%,较未处理样品增加41.29%,较直接冷冻-解冻样品的提取率增加25.16%。     

Comparison of the Stability of Pelargonidin-based Anthocyanins in Strawberry Juice and Concentrate

Strawberries were processed into juice (8° Brix) and concentrate (65° Brix) and different lots were fortified with pelargonidin 3‐glucoside, pelargonidin 3‐sophoroside, and acylated pelargonidin 3‐sophoroside 5‐glucoside. Changes in pigment concentration, color (CIE L*a*b*) and ascorbic acid content were monitored during storage at 25 °C. Anthocyanin and ascorbic acid degradations followed 1^st order reaction kinetics. Fortification increased the half‐life of the pigments from 3.5 to 5 d in concentrate and from 5 to 12 d in juice. The half‐life of ascorbic acid was 2 d in juice samples and ranged from 3 to 10 d in concentrate samples. Both systems showed changes in chroma and hue angle, but maintained L* values.     

红树莓果汁澄清剂的选择及澄清工艺的优化

以红树莓果汁为实验材料,选用壳聚糖、明胶、PVPP、果胶酶、皂土五种澄清剂对红树莓果汁进行单因素试验,以红树莓果汁的透光率为指标对比五种澄清剂的澄清效果;从中选择澄清效果较好的澄清剂,再通过正交优化试验筛选出红树莓果汁最佳的澄清工艺条件。结果表明,在单因素试验中,5种澄清剂对红树莓果汁都具有一定程度的澄清和脱色作用,壳聚糖和明胶的对红树莓果汁的澄清效果较好,PVPP和皂土次之,果胶酶的澄清效果不佳;通过正交优化试验和验证试验得出壳聚糖在质量浓度1.8 g/L、澄清温度40℃、澄清时间36 h的条件下澄清效果最佳,可以得到清澈透明且均一稳定,透光率达96.7%的红树莓果汁。该工艺可为红树莓资源的综合开发利用提供参考。     

热和紫外辐照对红莓花色苷稳定性的影响

研究了热和紫外辐照对红莓花色苷提取物稳定性的影响。结果表明,红莓花色苷受热(45～75℃)影响发生降解,其含量及红值均发生显著下降,75℃受热10h条件下,花色苷残留率仅为74 93% ,红值保留率为83 0 3% ,色泽变化(△E)为2 4 6 16。并发现红莓花色苷受热降解的反应符合一级反应动力学,其相关系数为0 984 7。通过对降解自由能的比较发现,红莓花色苷(E0 =8 33×10 4kJ/mol)比杨梅花色苷(E0 =343 4 6 4kJ/mol)有更好的热稳定性。2 5 4nm下的紫外辐照也会影响红莓花色苷的稳定性,但其表现的降解趋势与受热降解不同。     

贮藏温度对蓝莓汁单个花色苷降解的影响

为了探讨贮藏温度对蓝莓汁花色苷降解的影响,本文研究了蓝莓汁在4、25、37℃贮藏120期间色泽的变化以及贮藏期间总花色苷和单个花色苷的变化规律,并在此基础上研究了花色苷的降解动力学。结果表明,在4℃下蓝莓汁颜色保存较好,25、37℃变化较大,而贮藏期间总花色苷和单个花色苷呈下降趋势。与零级动力学模型相比,总花色苷和单个花色苷在25、37℃下的降解更符合一级动力学模型,4℃总花色苷的降解与零级和一级动力学模型拟合系数小,单个花色苷中有4种符合一级动力学模型,且温度越高,花色苷的一级降解动力学常数越大,降解速度越快,半衰期越短。含有半乳糖苷的花色苷,其半衰期较阿拉伯糖苷的花色苷略长。总之,蓝莓汁色泽的改变与花色苷的降解密切相关,在较低温度下贮藏,可以明显减少花色苷的损失。     

Anthocyanin Analysis as a Measure of Glycosidase Activity in Enzymes for Juice Processing

A screening procedure combining HPLC and spectrophotometric analyses was developed to measure glycosidase activity of enzyme preparations used for juice processing. Enzyme preparations (27) were evaluated; several contained β-galactosidase activity which can decompose cranberry juice pigments. β-galactosidase and α-arabinosidase activities were also determined using standard procedures (nitrophenol glycosides as substrates). Comparative results showed inconsistencies between the two procedures. Cranberry juice processing demonstrated that some enzyme preparations could decompose anthocyanin pigments under processing conditions. Pigment loss was much higher when enzymes were used with juice than with crushed fruit.     

影响草毒果汁红色素变化的因子研究

通过试验对草莓果汁在加工及继后贮藏过程中,影响红色素变化的因子进行了研究。结果表明,迅速加热果实温度到60℃,有利于提高果汁中红色素含量;向果汁中分别加入0.1%~0.4%的抗坏血酸、酒石酸和柠檬酸对果汁具有明显的增色作用;而加入1.0%~15.0%的葡萄糖和蔗糖对果汁颜色没有影响;调整果汁pH值到4.0以下有助于保持果汁的固有颜色;采用低温避光贮存果汁可延缓草莓果汁红色素的降解。     

响应面法优化蓝靛果红树莓复合发酵汁的研究

蓝靛果和红树莓是富含花青素类的小浆果。该研究以蓝靛果和红树莓为原料,以耐高糖安琪酵母为接种菌,制备复合发酵汁。考察浆果配比、酵母接种量、发酵温度和发酵时间对复合发酵汁中花青素含量的影响。通过单因素和响应曲面试验确定最佳工艺条件为:蓝靛果和红树莓的质量比例为3.23∶1、酵母接种量为1.27%、发酵温度为28℃、发酵时间为8 d。在此最佳工艺条件下,花青素含量为8.91 mg/mL,较鲜浆果汁提高了71.35%;DPPH自由基清除率为(97.41±0.4)%,O2-·清除率为(98.21±0.4)%,·OH清除率为(95.56±0.4)%,蛋白酶活力为(9.42±0.2)U/mL,超氧化物歧化酶活力为(82.45±0.4)U/mL。     

红树莓花色苷含量测定及成分分析

运用HPLC-DAD-ESI-MS技术建立了测定红树莓花色苷含量的方法,并确定了花色苷的成分组成。采用Zorbax SB-C18色谱柱(250 mm×4.6 mm,5μm),甲醇-5%甲酸水溶液为流动相,流速为1.0 mL/min,检测波长为520 nm,以矢车菊素-3-葡萄糖苷为对照,用外标法定量,并通过紫外扫描光谱信息和ESI+碎片离子信息对花色苷组成成分定性分析。结果表明:红树莓总花色苷含量为105.69 mg/100 g,其主要含有的4种花色苷成分为矢车菊素-3-槐糖苷、矢车菊素-3-槐糖-5-鼠李糖苷、矢车菊素-3-葡萄糖苷、矢车菊素-3-芸香糖苷,相对含量分别为22.05%、13.83%、33.74%和30.38%。     

树莓红色素的提取及稳定性的研究

本文研究了树莓红色素的树脂法提取工艺,通过4种树脂对树莓红色素的吸附及不同浓度的乙醇对树莓红色素解吸的比较研究,结果表明,AB-8树脂对树莓红色素具有较高的吸附量,用90%乙醇为洗脱剂得到的产品质量好;产品收率达1.84%。同时,对树莓红色素的性质,稳定性也进行了研究,结果证明此色素有较高热稳定性,光稳定性及一定的抗氧化能力,具有良好的开发价值。     

运用Mix-D-optimal设计开发紫甘蓝花色苷抗氧化复合果蔬汁饮料

优化紫甘蓝花色苷复合果蔬汁饮料的配方,并测定其抗氧化性.运用Mixture-D-optimal设计,以糖酸比为响应值,在未添加其他添加剂的条件下,利用苹果汁、黄瓜原汁和紫甘蓝花色苷三种原汁自身的糖、酸及风味物质进行复合,形成酸甜适口、风味相容的粉色复合果蔬汁饮料.实验结果表明:紫甘蓝花色苷抗氧化复合果蔬汁饮料的最佳配方...     

红树莓果汁降酸发酵过程中活性成分的变化

为研究陆生伊萨酵母(Issatchenkia terricola)WJL-G4对红树莓果汁降酸发酵过程中活性成分的影响,以接种红树莓果汁为处理组,以未接种的红树莓果汁作为对照组,测定总酚、总黄酮和花色苷的含量,采用高效液相色谱法对活性成分进行定性和定量分析,分析发酵过程与成分之间的相关性.结果表明:处理组和对照组的总酚...     

基于响应面法黑树莓果汁微胶囊化工艺优化

以黑树莓果汁为芯材,海藻酸钠、壳聚糖为壁材,采用锐孔-凝固浴法对黑树莓果汁进行微胶囊化。运用Box-Behnken中心组合设计和响应面分析,对影响黑树莓果汁微胶囊化主要因素即壁材芯材配比、海藻酸钠质量分数、壳聚糖质量分数进行多项式回归模型建立和最优化。结果表明：在壁材海藻酸钠/芯材4.05、海藻酸钠质量分数2.27%、壳聚糖质量分数1.28%时,黑树莓果汁微胶囊的包埋效果最好,包埋率可达87.15%。     

树莓汁中键合态香气物质提取方法及糖基组成的研究

本文采用Amberlite XAD-2树脂吸附洗脱分离的方法和甲醇直接提取法对树莓汁中的键合态香气物质进行了分离,对得到的键合态香气物质进行了酶水解释放,采用GC-MS分析方法对水解得到的键合态香气物质进行了分析鉴定,重点比较了这两种方法的提取效果,并对酶水解后的糖基部分进行了分析研究。结果显示,甲醇直接提取法只提取得到4种键合态香气物质,总含量为77.1μg/kg,包括2种苯系物和2种脂肪醇类物质;Amberlite XAD-2树脂吸附洗脱提取法共提取得到20种键合态香气物质,包括11种苯系物,6种醇类物质及3种萜烯类物质,总含量达3042μg/L。两种方法提取得到的键合态香气物质在种类和含量上存在很大的差异,Amberlite XAD-2树脂吸附提取法提取得到的键合态香气物质种类丰富。树莓汁中糖苷键合态香气物质的糖基部分含有甘露糖和葡萄糖两种单糖。     

鲜橙汁冷藏期间色泽变化研究

在4℃条件下贮藏鲜橙汁12 周期间,橙汁的红绿值a*、色泽指数OJ 值减小,亮度值L*、黄蓝值b*,饱和度C* 以及色调Hue 增大,Δ E* 值显著增大(P ＜ 0.05),橙汁色泽显著变差。同时,橙汁中类胡萝卜素和VC含量不断降低,褐变指数上升。橙汁色泽参数变化与类胡萝卜素和VC 含量的变化呈显著正相关,与褐变指数呈显著负相关。在4℃冷藏条件下贮藏鲜橙汁,其色泽的保质期为7～9 周。     

Characterization of Red Raspberry (Rubus idaeus L.) Genotypes for Their Physicochemical Properties

ABSTRACT:  The worldwide tendency for growing more small fruits, including raspberries, shows permanent increase because this group of fruits has a relatively higher content of bioactive nutrients. To study the health benefits of red raspberry fruits, 11 preselected wild-grown and 1 well-known cultivar, Heritage, were evaluated for some of their physicochemical properties such as fruit weight, total antioxidant capacity (measured by β-carotene bleaching and FRAP assays), total phenolics, ascorbic acid, soluble solid content (SSC), and acidity. Fruit weight, SSC, and ascorbic acid contents were between 1.47 and 2.32 g, 10.87% and 13.60%, and 21 and 36 mg/100 g, respectively. Antioxidant activity and total phenolic content varied among genotypes and the ERZ5 genotype had the highest antioxidant capacity as ascertained by both methods. This genotype also had the highest total phenolic (2031 μg GAE/g FW) content. There are linear relationships between antioxidant capacities and total phenols. The present study demonstrates the potential of certain wild genotypes, notably ERZ5, for improving the nutritional value through germplasm enhancement programs.